The food and beverage industry is under unprecedented pressure to innovate: cleaner labels, reduced processing, lower emissions, and more sustainable supply chains.

Yet many of the technologies underpinning modern food production — especially filtration and purification — still rely heavily on petroleum‑derived polymers and harsh chemical solvents.

At King Abdullah University of Science and Technology (KAUST), Professor Suzana Nunes, a leading researcher in environmental science and engineering, believes this dependency is no longer tenable. Her team has developed a new class of membranes made entirely from plant‑derived materials, offering a scalable, high‑performance alternative to conventional filters used in juice clarification, dairy processing and other liquid‑purification steps.

These membranes, fabricated using natural compounds such as thymol (from thyme) and vanillin (from vanilla), promise to remove cloudiness, suspended solids and unwanted macromolecules — all without heat, without harsh solvents, and without degrading nutrients or flavour compounds.

During our discussion, Dr Nunes explains the science behind the breakthrough, the sustainability implications, and the commercial pathway that could bring plant‑based membranes into mainstream food and beverage operations.

Replacing fossil‑derived membranes

For Nunes, the motivation to rethink membrane materials began with a growing global concern: the dominance of fossil‑derived polymers in filtration and the environmental consequences of their waste streams.

“Our main motivation is the growing concern on the excessive dominance of polymeric materials produced by fossil feedstock… and the consequences of their waste to the environment,” she explains. “Regulations on the use of chemicals, including polymeric materials, are becoming stricter. However, the industry is not ready for that.”

The challenge is twofold:

1. Fossil‑based membranes are deeply entrenched — decades of optimisation have made them cost‑effective and reliable.
2. Any alternative must match or exceed their performance, especially in demanding food and beverage environments.

This is why Nunes’ team focused on poly(ethylene furanoate) (PEF), a polymer that can be produced entirely from biomass and is considered a potential substitute for PET due to its stability and strength.

“We reached performances comparable to the best commercial ultrafiltration membranes but using bio‑sourced materials for the fabrication,” she says.

How plant‑based membranes work

Conventional ultrafiltration membranes resemble a sponge with a gradient of pore sizes: tiny pores at the top for selectivity, larger pores beneath for mechanical stability and flow.

Nunes’ team replicated this architecture using PEF and natural solvents — a major scientific achievement given the difficulty of dissolving PEF without harsh chemicals.

“PEF like PET is difficult to dissolve in regular solvents and even more identifying a green solvent was a big challenge,” she notes.
“The solvents we used are solid at room temperature… but when heated above their melting temperature they effectively form PEF solutions which remain stable for membrane casting.”

The resulting membranes:

• Filter at room temperature, preserving nutrients and flavour compounds.
• Reject macromolecules and turbidity‑causing particles, producing clearer juices and more stable dairy streams.
• Avoid heat‑based degradation, a major advantage for vitamins, proteins and delicate flavour compounds.

As Nunes puts it: “Nutrients and flavour compounds… are small molecules and easily pass through the membrane pores. Larger particles responsible for turbidity are rejected.”

Why thymol and vanillin?

The choice of thymol and vanillin is not simply about sustainability — it is about chemistry.

“They dissolve the polymer (PEF) by forming new hydrogen bonds and disrupting the polymer‑polymer internal packing,” Nunes explains.

This ability to dissolve PEF without petroleum‑derived solvents is what makes the entire membrane‑fabrication process possible.

Sustainability impact

One of the most compelling findings from the KAUST research is the quantified environmental benefit.

“The use of biomaterials we propose would reduce the global warming potential (GWP) by 42% compared to a fossil‑based counterpart,” Nunes says.

This reduction comes from renewable polymer and solvent sources, lower energy requirements in production, reduced chemical waste and potential biodegradability improvements.

The manufacturing process itself remains similar to industrial membrane fabrication — a deliberate choice to ensure scalability.

“We invest in developments that would be feasible in large scale,” she emphasises.

Scalability

Thymol and vanillin are already produced at industrial scale for pharmaceuticals, cosmetics and food applications. Thymol alone represents a global market of US$108 million, according to Global Market Statistics.

However, Nunes acknowledges that widespread adoption would require increased production.

“If the application as solvent would be implemented even beyond membrane fabrication, this would demand a production growth.”

Still, she believes the shift to bio‑based materials in filtration is inevitable:

“It is probably a question of when and not if the membrane industry will shift to bio‑based or at least less toxic solvents.”

Beyond juice clarification

While fruit juice clarification is an early and obvious application, Nunes sees far broader potential.

“Membrane technology is highly used in food industry. Juice clarification is just one of them.”

Her team’s current membranes operate in the ultrafiltration range, but she expects future versions to reach nanofiltration — unlocking even more applications.

Dairy processing

Membranes are already central to cheese manufacture and whey valorisation. Plant‑based membranes could:

• Concentrate milk proteins more sustainably
• Preserve flavour and texture in premium cheeses
• Extend shelf life through gentler purification
• Reduce waste streams such as whey

“Ultrafiltration membranes concentrate milk proteins before cheese making, preserving flavour and improving consistency in premium soft cheeses like camembert and brie.”

Beverage innovation
Membranes can:

• Produce alcohol‑free beer
• Clarify wine
• Purify oils
• Concentrate functional beverages without heat
• Reduce water content for transport without nutrient loss

Heat‑sensitive products
This is where membranes shine.

“Imagine the concentration or separation of vitamins or other components that would degrade at high temperature,” Nunes says. “Membranes can provide unique routes of processing them.”

From lab to factory floor

The pathway to industrial adoption is clear but requires several steps.

1. Polymer production
PEF is only now entering commercial production and remains a niche material.

“This is the first challenge,” Nunes notes.

2. Process optimisation
The membrane fabrication process must be refined for industrial machines, particularly coagulation bath conditions, solvent composition and continuous casting parameters.

KAUST can already fabricate membranes on semi‑technical machines, but this specific membrane is still in early development.

3. Regulatory approval
Food‑contact materials require rigorous certification.

“Authorisation or regulatory approval is also required,” she says.

4. Equipment compatibility
Fortunately, the membranes fit existing modules.

“These membranes would not be different in terms of module configuration than those already existing.”

5. Industry feedback
Nunes has decades of experience collaborating with membrane producers and understands the commercial pressures.

“We are aware of critical challenges and mostly propose solutions that could be easy to scale.”

Broader implications

Plant‑based membranes align with several major industry trends:

Cleaner labels & minimal processing
Membranes enable purification without heat or chemicals — a major advantage for brands seeking “natural”, “cold‑processed” or “nutrient‑preserving” claims.

Reduced food waste
Better purification and stabilisation can extend shelf life and reduce spoilage.

Water & energy efficiency
Membranes reduce energy use and enable concentration of beverages for transport.

Waste stream valorisation
Whey, for example, becomes a valuable ingredient rather than a disposal challenge.

Sustainability standards
As regulations tighten, plant‑based membranes could help manufacturers meet new requirements for renewable materials and lower emissions.

Sustainable materials for resilient food systems

For Nunes, this research is part of a broader mission at KAUST.

“Research on biomaterials for membrane fabrication is highly relevant in terms of sustainability, environment, material science and implementation of efficient and competitive industries,” she says.

Saudi Arabia’s dairy industry, for example, operates under water scarcity — making membrane‑based processing essential.

“Membranes could benefit in many other ways in emerging food manufacture, distribution and security,” she adds.

Ultimately, the goal is to enable a future where food systems are more efficient, less wasteful, less dependent on fossil materials and better aligned with environmental priorities.

“This research definitely fits perfectly into KAUST’s broader vision for sustainable materials and resilient food systems.”

A turning point

KAUST’s plant‑based membranes represent a rare combination of scientific innovation, sustainability impact and commercial relevance. They offer:

• Comparable performance to petroleum‑derived membranes
• A 42% reduction in global warming potential
• Compatibility with existing equipment
• Clear benefits for juice, dairy, wine, beer, oils and functional beverages
• A pathway toward cleaner labels and gentler processing

While commercialisation will take time — particularly as PEF production scales — the direction of travel is unmistakable. As Nunes puts it, the shift to bio‑based filtration is not a question of if, but when.